iBattz has expanded its iOS battery lineup with the introduction of the Mojo Removable Power Card Wallet ($50) -- a credit card-sized battery pack that's unique not only because of its size, but also because the 1500mAh battery inside can be swapped on the fly. It's just thick enough for a USB port, charging an iPhone or iPod at full speed, but iBattz doesn't include a Dock Connector cable. Available in white and black, it does come with a short Micro-USB to USB cable for recharging the battery itself.

The Mojo Removable Power Card Wallet is reminiscent of a third-generation iPod nano, specifically because of the housing’s reflective metal bottom. The top, as well as the edge with the USB ports, are covered in glossy white plastic, and the whole thing is about as small as it can be at only 3.5” long and 2.2” wide. A door on the top opens to reveal the battery inside: we’re pretty sure that it was supposed to stay attached where it pivots, but it usually snaps off when lifted, and back into place just as easily. The battery can be lifted out with a fingernail, or by just giving the back a tap.

The battery is the same as the one the company uses in its Removable Battery Case, and in fact the company advertises this battery pack as an accessory for that case. In our initial testing about a year ago, we were really surprised by how well the 1500mAh cell performed: it was able to deliver an iPhone 4 recharge of 85%, which is still the best performance we’ve seen from a battery of this size. That’s why we were somewhat disappointed by this unit’s results; it was only able to deliver a 62% charge to an iPhone 4S, which is not only significantly lower than before, but also one of the lowest recharges we’ve seen from any 1500mAh battery.

iBattz got the concept and size right here; Mojo Removable Card Wallet is a useful tool on its own, and in conjunction with the company’s battery case. The charger itself looks nice, and the 1-Amp output limitation isn’t surprising for a device of this physical size and capacity. However, the less than thrilling recharging performance and the slightly elevated price earn Mojo Removable Card Wallet a limited recommendation. There’s definitely some value here, especially for users who already bought into the iBattz ecosystem, but as a standalone device, it’s somewhat underwhelming.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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